Triple Michelson Interferometer for a Third-Generation Gravitational Wave Detector

TL;DR

This paper discusses the potential advantages of a triangular triple Michelson interferometer design for third-generation gravitational wave detectors, highlighting its benefits and contextualizing it within recent technological research.

Contribution

It reviews the old proposal of a triple Michelson interferometer, clarifies terminology, and advocates for this design as a promising foundation for future gravitational wave detectors.

Findings

Triangular configuration offers benefits over traditional designs.

The design is suitable for new detector sites with fewer constraints.

It provides a promising starting point for third-generation detectors.

Abstract

The upcoming European design study `Einstein gravitational-wave Telescope' represents the first step towards a substantial, international effort for the design of a third-generation interferometric gravitational wave detector. It is generally believed that third-generation instruments might not be installed into existing infrastructures but will provoke a new search for optimal detector sites. Consequently, the detector design could be subject to fewer constraints than the on-going design of the second generation instruments. In particular, it will be prudent to investigate alternatives to the traditional L-shaped Michelson interferometer. In this article, we review an old proposal to use three Michelson interferometers in a triangular configuration. We use this example of a triple Michelson interferometer to clarify the terminology and will put this idea into the context of more recent research on interferometer technologies. Furthermore the benefits of a triangular detector will be used to motivate this design as a good starting point for a more detailed research effort towards a third-generation gravitational wave detector.